Hybrid View
-
21-03-2014 #1
If you are going to replace the power supply to give a bit more grunt, then it's generally best to avoid switch-mode psu's. Use a simple linear design - traditional transformer/rectifier/capacitor. What you need is the peak current capability that the big smoothing cap gives (which may be over the steady current rating of the transformer) rather than the stabilised output of the switch-mode psu which can't handle pulse current demands very well. Watch output voltage, though, as combination of low-load output plus back emf of motors can make output transistors go pop.
Not many people build their own electronics - most people seem to stick to the mechanical bits - so good luck with it.
-
22-03-2014 #2
Thanks Lee for the moving of the post and thanks to Neale, irving and Jazzcnc for information.
Yes I realise that I am still on a learning curve but with the response received I am willing.
Up to now it was a tremendous experience, making all the components for a cnc engraver.
Not only the making of components but a human interface that it created. Free advise, free scrap aluminium and free assistance.
The volt/ohms value of the steppers are so low so I thought that keeping the supply low will assist in limiting the wattage. I presume the stepper values are kept low to keep inductance low.
What seems to come out of the discussion is that higher voltage, ordinary transformer power supply and current limiting will be the answer. (thanks Neale for the SMPS tip)
My power supply is not built yet so any voltage is possible. I am going to start off with an existing, 20Volt/5Amp, CC-CV, bench power supply.
My home made driver PCB does not have built-in current limiting, hmmm, I should incorporate it in the next version. I do have fly-back diodes on the motor leads for the back emf. BTW I am using PCB SPRINT Layout software, available from Abacus in Germany.
Again thanks for all the replies, much appreciated.
I will post the progress.
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
NEW MEMBER: Hello from South Africa
By Les Bidgood in forum New Member IntroductionsReplies: 7Last Post: 14-06-2013, 05:24 AM -
NEW MEMBER: New Member. Greeting from South Africa
By Les Bidgood in forum New Member IntroductionsReplies: 3Last Post: 02-04-2011, 04:44 PM -
NEW MEMBER: Hello from me, Ivan and sunny South Africa.
By itzar in forum New Member IntroductionsReplies: 1Last Post: 20-11-2010, 12:40 AM -
NEW MEMBER: Hello from South Africa
By rotacraft in forum New Member IntroductionsReplies: 1Last Post: 19-09-2010, 01:52 AM -
NEW MEMBER: hello from down south
By geza in forum New Member IntroductionsReplies: 4Last Post: 04-09-2010, 08:58 AM
Bookmarks